Swiss startup Vitality Vault got here out of stealth mode in 2018, and has been on an upward trajectory since then. The corporate created a system to retailer electrical energy by elevating concrete blocks, and traders rapidly jumped on board: Vitality Vault raised $110 million from the SoftBank Imaginative and prescient Fund in 2019, and one other $100 million led by Prime Movers Lab in 2021. It appears they’ve put that funding to good use, as a result of final week the corporate introduced commissioning of their first grid-scale power storage system exterior Shanghai, China.

The system is sort of a strong model of pumped hydro, which makes use of surplus producing capability to pump water uphill right into a reservoir. When the water’s launched it flows down via generators, making them spin and generate power.

Vitality Vault’s strong gravity system makes use of large, heavy blocks manufactured from concrete and composite materials and lifts them up within the air with a mechanical crane. The cranes are powered by extra power from the grid, which could be created on very sunny or windy days when there’s not lots of demand. The blocks are suspended at elevation till provide begins to fall wanting demand, and once they’re lowered down their weight pulls cables that spin generators and generate electrical energy.

As a result of concrete is denser than water, it takes extra power to raise it, however meaning it’s storing extra power too. The cranes are managed by a proprietary software program that automates most points of the system, from choosing blocks to lift or decrease to balancing out any swinging movement that occurs within the course of.

The power exterior Shanghai has a capability of 100 megawatt hours (MWh); it may possibly repeatedly discharge 25 megawatts for as much as 4 hours. That’s comparatively small—for comparability’s sake, the Ludington pumped storage plant in Michigan has a capability of 1,875 megawatts, which may energy a group of about 1.4 million folks. Vitality Vault says that subsequent gravity storage services it plans to construct will be capable to run at gigawatt-hour scale for 12 hours.

The Shanghai facility was constructed subsequent to a wind farm and a nationwide grid interconnection web site. The corporate says the power can have a round-trip effectivity above 80 % (which means that 80 % of the power expended to raise the blocks will likely be retained and translated to power output when the blocks are lowered). That’s akin to utility-scale batteries and pumped hydro.

One benefit the gravity system has over batteries, although, is that its storage capability will keep extra constant over time. Batteries slowly degrade as they cost and discharge, till they turn into unusable and might be recycled. The gravity system will probably have an extended lifespan than grid-scale batteries, and is extra appropriate for long-term power storage—that’s, storing extra power for weeks or months slightly than hours or days. This sort of storage goes to turn into extra crucial as we improve our reliance on photo voltaic and wind energy.

Vitality Vault IPO’d in February of 2022 via a special-purpose acquisition firm deal. The corporate subsequently got here underneath fireplace from analysts who mentioned its price and effectivity claims had been flawed. Later within the 12 months, a analysis agency revealed a brief vendor report in regards to the firm, later retracting a few of the statements made. Vitality Vault’s inventory value plunged in mid-2022 and has but to get well.

These setbacks don’t appear to have deterred them an excessive amount of, although. They just lately signed an settlement to construct one other 100 MWh storage facility in China’s Hebei Province; they’re partnering with Pacific Fuel and Electrical Firm to construct a 293 MWh facility in Northern California; and are constructing a 440 MWh facility close to Las Vegas.

Time will inform whether or not gravity storage is a possible choice to assist us transition to renewables. Within the meantime, Vitality Vault says commissioning of the Shanghai facility will likely be full by the top of this 12 months.

Picture Credit score: Vitality Vault